334 Mary Davies Swartz, 



of a syringe, or intraperiioneally , by means of a needle and burette 

 with pressure-bulb attached, always under aseptic conditions. After 

 receiving injections, the animals were replaced in cages, and the 

 urine collected under toluene. The excess of toluene was removed, 

 at the time of examination, by means of a separatory funnel, and the 

 urine measured, filtered, and tested for reducing substances with 

 Fehling's solution. 



Qualitative tests for the carbohydrates were made in the following 

 manner: (l) for dulse and salep, by boiling a few drops of urine with 

 Fehling's solution, from which these hemicelluloses were precipitated 

 in fine white flocks, even if only traces were present; (2) for Irish 

 moss, by the reduction of Fehling's solution after hydrolysis of the 

 urine with dilute hydrochloric acid;' (3) for sinistrin, by the marked 

 increase in the levo-rotation of the urine. 



Isolation of the carbohydrates was accomplished by freeing the 

 urine from inorganic salts with lead acetate, removing the excess of 

 lead with hydrogen sulphide, and concentrating the salt-free solutions 

 to a small volume. Dulse and Irish moss were then precipitated with 

 absolute alcohol; salep with alcohol or Fehling's solution; sinistrin 

 with milk of lime, being freed from its calcium compound by the 

 method used in its preparation. ^ 



These substances were identified as carbohydrates, by their yield- 

 ing reducing sugar on hydrolysis; salep and sinistrin were further 

 identified by their levo-rotation, Irish moss by testing for mucic acid., 

 and dulse by testing for furfurol. 



Quantitative determinations of dulse, salep and sinistrin were made 

 by polariscopic examination in a 200 mm. tube, all samples of urine 

 being clarified with equal volumes of alumina cream. A satisfactory 

 quantitative method for the determination of Irish moss was not 

 developed. It proved impossible to estimate any of these carbohy- 

 drates quantitatively by the method of acid hydrolysis. In some 

 instances, especially with Irish moss, a trace of reduction was ob- 

 tained, but in most cases, the results were negative, although the hemi- 

 cellulose was known to be present.^ 



'Trial was made of Bauer's method (Zeitschrift fur physiologische Chemie, 51, 

 p. 158, 1907) of determining galactose in urine as mucic acid, by concentrating 

 100 cc.of urine with 25-35 cc. of concentrated nitric acid (sp. gr. 1.4) to a volume of 

 20 cc, but owing probably to the low percentage of galactose from the small amount 

 of Irish moss present, this test was unsatisfactor3\ 



2Cf. p. 315. 



^Samples were removed and tested every half hour for 2| hours. At the end of 

 1 hour they were usually neutral, or slightly alkaline in reaction. Addition of suf- 



